1. Field of the Invention
The present invention concerns a temperature-controlled fuel gas throughflow valve for a catalytic heating device.
2. Description of the Prior Art
With a known hair curler (German Offenleggungschrift No. 20 40 003), the fuel conveyance device is a nozzle situated between the fuel container and the combustion chamber. A stream or flow of gaseous fuel is conducted through this nozzle into the combustion chamber. By means of such an arrangement of the nozzle and of the fuel container, the conveyance quantity of fuel and of oxygen into the combustion chamber is supposed to be controlled in an extremely uniform and precisely dosed fashion.
A catalytic heating device is also known (U.S. Pat. No. 2,997,869), in which the methanol vapor and the air are conducted to a catalyst. Here, the fuel gas flows through a tubular body, at one of whose ends a rod is disposed coaxially with respect to the tubular body, which contains the catalyst. In this way, the rod-shaped body heats up when the catalytic combustion has started.
Finally, a hair curling unit is known (European Patent Application No. 0 021 224), in which a valve device is situated in the housing between the cylindrical rod body and the guide handle. This valve device regulates the outflow of the fuel gas from the fuel gas tank, which is housed in the handle section, to the catalyst, which is situated in the rod body. This regulation here takes place in dependence on a bimetallic element and furthermore in dependence on a positioning member which can be activated manually. This known hair curling unit, according to the type of a curling iron, has the disadvantage that the accuracy of the regulation depends significantly on the quality of the material used for the handle section because, on the one hand, the associated valve device is situated in the handle section and, on the other hand, the bimetallic element is connected with the cylindrical rod body. Experience has shown that the handle section and the rod body shrink or elongate under the influence of temperature and/or humidity. As a consequence, the temperature is not maintained precisely, which can cause damage to the hair.